Examples of Jean Brueil marks:

Post 1900 (PT powder) but pre mid 1912 (Chamber length 7.5 marked in cm). Bore is 19.2 (10 gauge):


Post mid-1912. Bore is 18.4 (12 gauge); chamber length is 70mm. J.G. is the gun maker. J.B is the mark for Brueil post WWI.


This line "Dating Early 20th Century French Shotguns" might help. You'll note that Didier-Drevet was the only component maker (barrels) who dated his products in St. Etienne and he did so from 1854 to 1930s which enabled us to at least identify when St. Etienne changed from mm to cm (1889) and back to mm (1912) for chamber length:
https://www.doublegunshop.com/forums/ubbthreads.php?ubb=showflat&Number=484199

As a consequence we were able to at least verify somewhat the Darnes SN date chart (that as Ted points out has a lot of exceptions in it):


Here is Ted's "Darne Patent Tree"

Last edited by Argo44; 12/15/19 11:05 AM.
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